IK Multimedia iLoud Precision MTM

IK’s affordable iLoud range has grown into a serious monitoring tool. We put their new flagship to the test.

With their iLoud range, IK Multimedia have carved out a niche for ultra‑compact yet high‑performance active monitors created using injection‑moulded plastic enclosures and, in the case of the iLoud MTM, with integrated ARC room optimisation. The iLoud Precision MTM subject of this review marks a significant departure, because while the integrated room optimisation remains, ultra‑compact dimensions and plastic enclosures have given way to more traditional proportions and wood‑panel construction.

The iLoud Precision MTM is the largest of a new range that also includes the smaller iLoud Precision 5 and iLoud Precision 6. Each monitor ships with an IK Multimedia MEMS (Micro Electro Mechanical System) ARC 3 measuring microphone and a set of four monitor isolation pads. Simultaneously, IK Multimedia have also launched a standalone X‑Monitor Windows and Mac OS app. X‑Monitor provides monitor configuration functions (so no more reaching around the back to fumble with EQ switches), manages firmware updates, provides a range of default monitor EQ profiles, and also plays the role of front end for ARC 3 room optimisation. So, together with the monitor itself, I’m not short of things to write about. I’ll start with the monitor.

Precision Engineering

As its name suggests, the Precision MTM is a D’Appolito‑format monitor that incorporates twin 130mm bass/mid drivers located above and below a 38mm shallow‑waveguide‑loaded textile‑dome tweeter. The system is reflex loaded by a rear‑mounted and generously flared port. The Precision MTM cabinet is of MDF construction and not entirely rectilinear, flaunting some subtle curves. The cabinet is finished in a conservative ‘studio black’ textured paint. It feels substantial, and its relatively large and slightly curved side panels respond to a knuckle rap with a satisfying dull and non‑resonant thunk. Precision MTM amplification comprises 145 Watts and 30 Watts of Class‑D power respectively for the bass/mid drivers and the tweeter. The big difference in rated power specification between the drivers serves to illustrate how much more sensitive the latter is than the former.

The bass/mid drivers feature a coated diaphragm that IK Multimedia describe as “ultralight”, and the tweeter features a chamber behind the dome that serves both to lower the driver’s fundamental resonance and to attenuate energy radiated from the rear of the diaphragm. Beyond that, IK Multimedia offers no particular details on the drivers that might suggest they’re anything but conventional. The crossover between the drivers is at 1900Hz and has extremely steep, eighth‑order (48dB/octave) filter slopes. These steep slopes are made feasible by the Precision MTM being very much a monitor of the DSP age. Its DSP runs internally at 96kHz, and along with the crossover functions, it implements the ARC 3 features, the rear‑panel EQ options and the USB‑enabled integration with the X‑Monitor app. The DSP also enables wide‑band time‑domain correction that helps ensure that, on its reference forward axis, the Precision MTM’s phase response stays within ±20 degrees from 150Hz upwards. Control of phase response should help ensure that, on‑axis at least, the Precision MTM will produce notably tight time‑domain performance. This ought particularly to benefit stereo imaging, as our ears rely significantly on timing clues in order to identify audio source position.

Considering the all‑digital internals of the Precision MTM, it’s slightly surprising that it offers only an analogue input, on a balanced combi XLR/TRS jack socket. There’s no digital input of any type. The rear‑panel EQ switches, duplicated within the X‑Monitor app, offer low‑frequency extension and shelf adjustments, desk EQ options, midrange boost and cut, and high‑frequency shelf adjustment. X‑Monitor additionally provides a range of preset EQ profiles, using the five filter elements and designed for different installation scenarios: ‘Small Desk Wall’, or ‘Large Desk Corner’, for example. Alongside the rear‑panel EQ switches are an input sensitivity adjustment control, an input socket for the ARC 3 measuring microphone, and a CAL button that enables the integrated ARC 3 room optimisation to be managed from the monitor rather than from the X‑Monitor app. There’s also 3.5mm jack socket present to connect an optional wired remote control, which offers a non‑app means of switching monitor EQ profiles.

ARC De Triomphe

Speaking of the X‑Monitor integrated ARC 3, if my memory serves me correctly, ARC was one of the first room‑optimisation products, and is now on its third major iteration. If you’re unfamiliar with the basic principle, it is to measure the frequency response that the combination of monitor and room acoustics generate, at and around the primary listening position, and then to use the power of DSP (sometimes within the DAW computer, sometimes within the monitor) to equalise the monitor’s inherent frequency response such that the room effects are corrected. Early versions of room optimisation routines were, I think it’s safe to say, relatively unsophisticated, but the field has developed rapidly, ARC 3 being an example of that development, and the technique has matured to become both effective and useful.

Critics of room optimisation, of which I have been one, sometimes point out a fundamental flaw, which is that it sacrifices the tonal accuracy of the direct sound of the monitors (ie. the sound that reaches the ears directly and hasn’t yet bounced around the room) in order to correct flaws that might be more appropriately fixed by room acoustic treatment. This, especially in the case of nearfield monitoring, can result in a skewed direct sound tonal balance and, potentially, compromised stereo imaging if the two monitors of a pair have significantly different room optimisation EQ applied. It’s ironic that monitor manufacturers such as IK Multimedia go to great lengths to ensure that pairs of monitors are closely matched for frequency response (matching speakers consistently within, say, 1dB of each other is perhaps the hardest of speaker manufacturing challenges), and then have us intentionally degrade that pair matching by applying different room optimisation EQ to each monitor of the pair. Perhaps this is telling us that stereo pair matching isn’t quite as important as we’ve always been led to believe?

Screen 1: The X‑Monitor app guides you through the process of measuring the monitors’ response in your room.

Using ARC 3 to optimise a pair of Precision MTMs for the room is quick and intuitive. The procedure first requires the supplied MEMS microphone to be plugged into the appropriate socket on the rear panel of one of the monitors. A standard XLR mic cable is used. The mic is then positioned on a stand at the listening position. Clicking on the X‑Monitor Calibrate button for the mic‑connected monitor then opens a dialogue box that confirms the presence of the mic and instructs on the four measuring positions required. Clicking on Capture Point, as illustrated in Screen 1, triggers a series of short sine sweep signals. When the response at the first measurement position has been captured, X‑Monitor instructs you to move the mic to the next position. The process is repeated for three further mic positions, following which an optimisation curve for the first monitor is generated. Repeating the whole process for the second monitor results in a stereo pair of room‑optimised monitors. Screen 2 shows the before and after optimisation response curves for one channel (the right) in my studio room. I’ve shown just one channel for clarity because the other channel was reasonably similar.

Screen 2: The pre‑ and post‑correction responses of a single Precision MTM.

The ARC 3 process is very slick and apparently works well, but I was particularly intrigued by a couple of aspects. Firstly, there’s no specific calibration of the MEMS measuring mic. Professional measurement microphones are usually supplied with serial‑number‑linked calibration curves (and data) so that they can be relied on to represent a known reference, but this is not the case with the ARC 3 MEMS mic. However, a MEMS mic is supplied with each Precision MTM, so to investigate how similar the two mics in my possession were, I sequentially measured a frequency response curve for one monitor using the two review microphones. The result was reasonably reassuring, with the maximum difference between the two mics being less than 1dB. The ARC 3 MEMS mic is not a professional measuring mic, but it’s adequate for the job.

The second intrigue is simply that X‑Monitor can treat each monitor of a pair independently. In my review of the Neumann KH150 I mention that Neumann’s MA 1 room‑optimisation app specifically doesn’t allow significantly different EQ to be applied to each monitor of a pair, because doing so would risk compromising the stereo performance. With ARC 3, however, it’s perfectly possible to apply different EQ profiles to left and right monitors, or even have room optimisation engaged on one monitor but not on the other. I can confirm doing any of these things can make a pair sound anything from slightly to extremely weird.

Speaker Profiles

In addition to enabling ARC 3, X‑Monitor also enables the selection of EQ profiles that IK Multimedia say are designed to mimic the frequency response and phase characteristics of a variety of different types of speakers — from portable Bluetooth boxes and TVs to generic hi‑fi speakers and classic pro monitors. There’s a total of 30 speaker profiles to choose from. In terms of both technical validity and operational utility I’ve personally never been entirely persuaded by this kind of speaker modelling. The idea behind monitoring for me is to provide a reference standard on which all downstream reproduction of the material in question is built. And part of the skill set of mix or mastering engineers is to know how to use the reference monitoring such that translation to downstream playback will work appropriately. Adding the option for 30 alternative performance profiles, which may, or perhaps may not, accurately reflect the performance of imagined downstream devices seems to me likely to provide a mechanism for doubt and prevarication in a mix or mastering session.

You might find that the facility X‑Monitor provides to make a pair of Precision MTMs pretend to be something they’re not is right up your boulevard, and while I can report that the functionality of selecting alternative monitor profiles works very well, and that listening to them is superficially interesting, it’s not something I think I’d use very often.

Phone Home

To illustrate X‑Monitor’s ability to model the response of different species of speaker, I used FuzzMeasure to generate a Precision MTM in‑room frequency response curve with the app’s ‘smartphone’ profile engaged. Then I measured an actual smartphone (my ancient iPhone 7; FuzzMeasure enables this by usefully providing the facility to import and analyse ‘field recordings’) in the same room, located at a position between the monitors. The result is displayed in Diagram 1 and, apart from a few localised differences, the two curves are remarkably similar. Furthermore, despite my philosophical doubts about the inherent value of making a pair of high‑performance monitors sound like an obsolete iPhone, my subjective response aligned pretty much with the objective measurement — the Precision MTMs did sound like my iPhone. It seems an oversight, though, that engaging the X‑Monitor smartphone profile doesn’t force it into a mono mode, because despite its two speakers, a smartphone is effectively a mono source unless you’re a bee, or maybe a small spider. Stereo combined with restricted smartphone bandwidth from the Precision MTMs sounded decidedly incongruous.

Diagram 1: The Precision MTM, measured using X‑Monitor’s ‘smartphone’ profile (red trace), and the response of a real iPhone in the same room (blue).

Continuing with FuzzMeasure analysis of the Precision MTM, Diagram 2 shows its axial frequency response along with second‑ and third‑harmonic distortion. The monitor output level was 90dB at 1m. The frequency response is impressively flat, with a hint of high‑frequency down‑tilt. Distortion is also well controlled, with the more troublesome third harmonic typically at between ‑50dB (0.3%) and ‑60dB (0.1%) below the fundamental above 100Hz. While not quite as impressive as the KH150, which boasts particularly impressive distortion performance, the Precision MTM nonetheless demonstrates distortion numbers that are highly competitive.

Diagram 2: The Precision MTM’s on‑axis frequency response (red), and harmonic distortion at 90dB SPL at 1m (second harmonics in green; third harmonics in blue).

Diagram 3 illustrates the Precision MTM axial and 30‑degree vertically off‑axis frequency response, and it provides a textbook example of the power of the D’Appolito format to narrow dispersion through the upper midrange, and similarly how the output of the relatively large tweeter dome falls away off‑axis above about 12kHz. Having pointed that out, I’d suggest it’s of more academic interest (no, really) than subjective significance. The D’Appolito midrange suck‑out is significant, however. It’s subjectively noticeable and makes the Precision MTM tonal balance a little variable with head position. Midrange balance dulls appreciably with head movement away from the central axis, which might sound like an issue — but if you’re aware of the effect, it can be factored in to working practices, and the midrange suck‑out probably reduces desk, floor and ceiling reflections in the critical midband.

Diagram 3: The on‑axis response (red) versus the response measured 30 degrees above and below (blue and yellow, respectively).

Diagram 4 looks somewhat of a jumble, but stay with me and I’ll explain. Each curve represents a frequency response captured with the measuring microphone very close to its specific subject. The green curve is the close‑mic response of one of the Precision MTM bass/mid drivers, and the dip at 40Hz reveals the system’s reflex‑port tuning frequency. The red curve, meanwhile, is the port output captured with the mic at the port mouth. Apart from the port output peaking, as expected from the green curve, at 40Hz, the red curve reveals some output from 500Hz and above that really ought not be present. It appears to be midrange energy ‘leaking’ out through the port, but of course it could potentially be ‘crosstalk’ from the forward output of the bass/mid drivers. So in order to check that, the blue curve was generated by leaving the mic at the port mouth but blocking the port itself (with a duster, now you’ve asked). It confirms that at least some of the output revealed in the red curve, especially the peak at 900Hz and above, is port output, because it’s attenuated when the port is blocked. Stopping midrange energy inside a cabinet from making its way out through the port is a significant challenge in two‑way ported speakers. Using an ABR (auxiliary bass radiator) rather than a simple port can be a solution, as can locating the port in the rear panel of the monitor, as is the case with the Precision MTM, where unintended output is made less troublesome, but port output such as displayed by the Precision MTM will potentially contribute to the subjective character of the monitor.

Diagram 4: Close‑mic measurements of a bass/mid driver (green), the port exit when left open (red) and when blocked (blue).

The final FuzzMeasure analysis, in Diagram 5, shows the Precision MTM step response. IK Multimedia display a step‑response curve on their website in order to promote the monitor’s phase‑corrected time‑domain characteristics, so I thought it would be interesting to see if I could duplicate it. The answer is yes: the Precision MTM does display a notably clean step response, especially in terms of its well‑damped low‑frequency ringing. I’ve displayed the step‑response data further along the time axis than is shown on IK Multimedia’s own curve because, just for interest, I wanted to include the arrival of the first room reflection at 37ms (22ms after the monitor output arrives).

Diagram 5: Precision MTM step response.

Final Thoughts

The Precision MTM, along with its partnering X‑Monitor app, packs in an awful lot of monitoring technology, but of course none of it would be worthwhile if it didn’t do a competent job of the fundamentals of monitoring. The Neumann KH150 and has set a particularly high bar for nearfield monitoring, but despite being less expensive, the Precision MTM was not remotely outclassed. The Precision MTM displays slightly more character in terms of tonal balance than the unfailingly neutral Neumann; there’s a hint of midrange coloration and I found the Precision MTM tweeter occasionally slightly attention‑seeking. The low‑frequency performance, though, is very strong. It displays usefully extended bandwidth, combined with an impressive ability to start and stop and securely reproduce pitch. High volume levels also are no problem for the Precision MTM. It can play satisfyingly loud without strain, and without appearing to change much in terms of its tonal character.

The low‑frequency performance is very strong: it displays usefully extended bandwidth combined with an impressive ability to start and stop and securely reproduce pitch.

As I mentioned earlier, the Precision MTM’s D’Appolito format is noticeable subjectively, and that leaves the monitors somewhat sensitive to setup in the room: ear position, especially for genuine nearfield monitoring, really needs to be on the tweeter axis. Stereo imaging is convincing, with good focus and portrayal of depth. I suspect this is partly a result of the D’Appolito format and partly a result of the Precision MTM’s phase‑corrected time‑domain performance — but low levels of distortion and coloration help too.

Adding ARC 3 and X‑Monitor to the mix uncovers a whole extra layer of performance and utility from the Precision MTM. As with any room optimisation system, the benefits it brings will tend to be related to the inherent acoustic quality of the room. If a room is already good, room optimisation will add little more than a final polish, but if the room is poor, it may well rescue the situation (although the best advice would always be to try to improve the room). In my room, ARC 3 helped clean up the low‑frequency performance and smooth out some inherent midrange character, but even so, the Precision MTMs were more than usable without it. And while I’ve expressed my uncertainty concerning the true value of all the alternative monitor profiles that X‑Monitor provides, I can’t help but acknowledge the way they have been so smartly integrated into the X‑Monitor user interface. I may wonder if 30 monitor profiles is a truly useful facility, but it is undoubtedly a very cool one.  

Information

€2399.98 per pair including VAT.

www.ikmultimedia.com

$2399.98 per pair.

www.ikmultimedia.com